Fix a missing letter in the documentation.

Hello,

I just found a missing letter in the PHP CI configuration documentation. This MR allow to fix that 😄 

See merge request !2519

Fix MR diff 'Edit' button

It now works and has the right size.

See merge request !2542

More highlighted diff fixes

See merge request !2545

Fix grammar and typos in file finder docs



See merge request !2547

[ci skip]

Make sure non-highlighted diffs are still escaped

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/12521

See merge request !2544

File finder can be invoked from anywhere!



See merge request !2543

[ci skip]

Add method to calculate total size of artifacts in subpath

See merge request !2500

Diff highlight themes

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/12484

See merge request !2530

Add housekeeping feature documentation

Add documentation about the new housekeeping feature in the project settings page.

See merge request !2371

[ci skip]

Add file finder documentation

Closes #7966 

See merge request !2541

[ci skip]

Milestone drag & drop cursor

Fixes #4097 

![grab-cursor](/uploads/f5071d7e4839c3b4b88c9f7f1270eee3/grab-cursor.gif)

cc @jschatz1 @creamzy 

See merge request !2532

Add basic documentation for build artifacts

/cc @axil @ayufan 

See merge request !2511

Add documentation on restarting GitLab

This will save as time from writing the same commands
over and over again.

See merge request !2510

[ci skip]

[ci skip]

Do not use progress bar when downloading build artifacts

Closes #12491

See merge request !2531

Remove execution permissions from font assets

[ci skip]

See merge request !2082

Init script changes for gitlab-workhorse in 8.4

Goes with https://gitlab.com/gitlab-org/gitlab-workhorse/merge_requests/31

Also bumps gitlab-workhorse to 0.6.1.

[ci skip]

See merge request !2529

Fix import of GitHub's wiki when the repository has not been created

Fixes #12503 

See merge request !2533

Fixes #4097

Closes #12491

Instrument Gitlab::Git::Repository



See merge request !2528